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How Do I Know If I Have Rats or Mice?

 

 

The most common signs of rats and mice are the evidence they leave behind, such as burrows, fecal droppings, tracks, chewed out holes in walls, chewed wires, urine stains and nesting materials. Rodents are more likely to be seen or heard shortly after dark and in the early morning.  The holes that rats chew in walls tend to be the size of a tennis ball (about 2” to 3” diameter)

    

Rat fecal dropping shown actual size         Mouse fecal dropping shown actual size

         

Rat chew in walls (2" to 3" diameter)         Active rat burrow

Rodent Burrows

Rodents use burrows to move from place to place. Burrows are typically found around concrete slabs and building foundations, under materials stored outdoors, and along fence rows. An active burrow entrance is usually seen as a hole in the ground, clear of leaves and debris. Active burrow runways are often clean and smooth, and frequently follow along a wall or fence.

To find out if the burrow is active, loosely fill the opening of the hole with dirt. If a rodent is using that burrow, the hole will reappear. Rodents cannot be eliminated by blocking their burrows. They can simply dig another burrow.


Last Modified: August 11, 2009
2100 Clarendon Blvd. Arlington, VA 22201 Tel: 703-228-3000 TTY: 703-228-4611